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Diffstat (limited to 'kernel/bpf/helpers.c')
-rw-r--r--kernel/bpf/helpers.c32
1 files changed, 24 insertions, 8 deletions
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index a05aeb345896..a0bf39b7359a 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -129,7 +129,8 @@ const struct bpf_func_proto bpf_map_peek_elem_proto = {
BPF_CALL_3(bpf_map_lookup_percpu_elem, struct bpf_map *, map, void *, key, u32, cpu)
{
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
+ !rcu_read_lock_bh_held());
return (unsigned long) map->ops->map_lookup_percpu_elem(map, key, cpu);
}
@@ -882,6 +883,13 @@ int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args,
if (fmt[i] == 'p') {
sizeof_cur_arg = sizeof(long);
+ if (fmt[i + 1] == 0 || isspace(fmt[i + 1]) ||
+ ispunct(fmt[i + 1])) {
+ if (tmp_buf)
+ cur_arg = raw_args[num_spec];
+ goto nocopy_fmt;
+ }
+
if ((fmt[i + 1] == 'k' || fmt[i + 1] == 'u') &&
fmt[i + 2] == 's') {
fmt_ptype = fmt[i + 1];
@@ -889,11 +897,9 @@ int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args,
goto fmt_str;
}
- if (fmt[i + 1] == 0 || isspace(fmt[i + 1]) ||
- ispunct(fmt[i + 1]) || fmt[i + 1] == 'K' ||
+ if (fmt[i + 1] == 'K' ||
fmt[i + 1] == 'x' || fmt[i + 1] == 's' ||
fmt[i + 1] == 'S') {
- /* just kernel pointers */
if (tmp_buf)
cur_arg = raw_args[num_spec];
i++;
@@ -1270,8 +1276,11 @@ static int __bpf_async_init(struct bpf_async_kern *async, struct bpf_map *map, u
goto out;
}
- /* allocate hrtimer via map_kmalloc to use memcg accounting */
- cb = bpf_map_kmalloc_node(map, size, GFP_ATOMIC, map->numa_node);
+ /* Allocate via bpf_map_kmalloc_node() for memcg accounting. Until
+ * kmalloc_nolock() is available, avoid locking issues by using
+ * __GFP_HIGH (GFP_ATOMIC & ~__GFP_RECLAIM).
+ */
+ cb = bpf_map_kmalloc_node(map, size, __GFP_HIGH, map->numa_node);
if (!cb) {
ret = -ENOMEM;
goto out;
@@ -2775,9 +2784,16 @@ static bool bpf_stack_walker(void *cookie, u64 ip, u64 sp, u64 bp)
struct bpf_throw_ctx *ctx = cookie;
struct bpf_prog *prog;
- if (!is_bpf_text_address(ip))
- return !ctx->cnt;
+ /*
+ * The RCU read lock is held to safely traverse the latch tree, but we
+ * don't need its protection when accessing the prog, since it has an
+ * active stack frame on the current stack trace, and won't disappear.
+ */
+ rcu_read_lock();
prog = bpf_prog_ksym_find(ip);
+ rcu_read_unlock();
+ if (!prog)
+ return !ctx->cnt;
ctx->cnt++;
if (bpf_is_subprog(prog))
return true;